#!/bin/bash

s1_generate_a_series_of_files(){
	for i in {1..100};do
		echo "$i" >> /tmp/new_file$i
	done
}

s2_list_4_files_in_long_format_about_account_and_group(){
	ls -l /etc/{passwd,shadow,group,gshadow} |sort -d
}

s3_find_items_related_to_given_username(){
	grep -h $1 /etc/{passwd,shadow} |sort -d
}

s4_find_items_related_to_given_group_name(){
	grep -h $1 /etc/{group,gshadow} |sort -d
}

s5_create_groups_for_given_group_names(){
	groupadd rnd
	groupadd itoperation
}

s6_create_users_and_set_their_group_as_required(){
	useradd -G rnd adam
	useradd -G rnd bob
	useradd -G itoperation calvin
	useradd -G itoperation david
	useradd -G rnd edward
}

s7_change_users_shell(){
	usermod -s /usr/bin/sh adam && usermod -s /usr/bin/sh edward
}

s8_set_password_change_policy(){
	passwd -n 10 -x 60 -w 10 adam
	passwd -n 10 -x 60 -w 10 bob
	passwd -n 10 -x 60 -w 10 david
	passwd -n 10 -x 60 -w 10 calvin
	passwd -n 10 -x 60 -w 10 edward
}

s9_set_password_for_five_users(){
	usernames=(adam bob calvin david edward)
	for i in $(seq 1 5);do
		echo ${!1}
		echo $(($i-1))
	done
	echo "${username[0]}:$1" | chpasswd
	echo "${username[1]}:$2" | chpasswd
	echo "${username[2]}:$3" | chpasswd
	echo "${username[3]}:$4" | chpasswd
	echo "${username[$(($i-1))]}:$5" | chpasswd
}

s10_lock_bobs_password(){
	usermod -L bob
}

s11_include_adam_into_wheel_group(){
	usermod -a -G wheel adam
}

s12_change_files_permission(){
	for i in {1..33};do
		chmod -R 640 /tmp/new_file$[3*i]
	done
}
